In recent years, a large number of poisonous heavy metal ions are contained in waste water discharged by industrial enterprises in China. A research hotspot in the technical field of water treatment is to effectively remove the heavy metal ions in the waste water. Antimony is a poisonous and harmful pollutant in water and has two existence forms: trivalent antimony and trivalent antimony, wherein the existence form of pentavalent antimony is more common. Compared with trivalent antimony, the pentavalent antimony has higher electronegativity and higher water solubility, which is difficult to be removed. At present, methods for removing antimony pollutants in water mainly include: an adsorption method, a coagulating precipitation method, an ion exchange method, etc. The above methods generally have better effect of removing the trivalent antimony, but are not effective in removing the pentavalent antimony.
An electrochemical method is an effective water purification technology, which is used for purifying the pollutants by an electrochemical reaction in the water and a single action or couple with other processes such as flocculation, precipitation, oxidation, reduction, etc. Authorized patents (201310059368.0 and 201310319985.X) and an application for patent (Application Number: 201510131879.8) disclose methods for removing pentavalent antimony by the electrochemical method. The pentavalent antimony is reduced to trivalent antimony by the electrochemical method, and then the trivalent antimony is removed by the combined action of adsorption, coagulation and coprecipitation. However, the patents need to add a DC (Direct Current) power supply for supplying power, thereby greatly increasing the treatment cost.